The invention relates to a glazing assembly and in particular to a glazing assembly for large-scale structural applications such as curtain walling and the like.
In conventional curtain walling systems the glazing units are retained by beads of aluminium extending around the periphery thereof. While such known systems are effective the use of such aluminium beads obscures the peripheral edge of the glazing and leads to sight lines that are not aesthetically attractive. In addition, such systems are relatively expensive and difficult to install.
WO-A-95/13439 describes a glazing unit comprising glass sheets which are said to be anchored to a support by fastening elements. A protector element has a U-shaped portion that extends around the edge of the inner pane and is placed to assist in spreading a sealing compound between the panes.
EP-A-628672 describes a glazing unit in which fixing elements are embedded in a sealing material between adjacent glass plates. The fixing element has a hook-like projection which is engaged in a slot formed in the external glass sheet.
GB-A-2167110 describes a glazing unit in which a channel shaped member is engaged in the edge of double glazed sheets. A holder is used to fix the channel shaped member in place. An elastic material is provided between the head of the holder and the channel shaped members.
WO-A-87-06644 A describes a glazing unit in which a resilient member is received between glass sheets and projects beyond the plates for anchoring to a building.
There are several problems with such conventional arrangements. In particular, because of the fixing means used it is generally not possible to guarantee the integrity of the seal. In addition, these systems are generally not practical as they require modifications to the glass and/or are difficult to fit effectively. Further, the retaining force is not effectively distributed in most cases. This invention is therefore directed towards providing a glazing assembly which will overcome at least some of these problems and which may consequently be used in a wide range of applications, especially for curtain walling and the like.
According to the invention there is provided a glazing assembly comprising a glazing unit having at least two sheets of glass, adjacent sheets being separated by a spacer means comprising an inner spacer bar and an outer seal extending around the periphery of the spacer bar and between the sheets of glass, and a fixing means for fixing the glazing unit to an adjacent support, in use, the fixing means comprising:
plurality of peripherally spaced-apart fixing inserts which are inserted into the outer seal leaving a depth of outer seal between the spacer bar and the inserts, each fixing insert defining a receiving slot and;
a toggle which is movable from a locating position for the insertion of the toggle to a locking position in which the toggle is engaged in the receiving slots of laterally adjacent fixing inserts.
The invention provides a glazing assembly with a highly efficient means for sealing and fixing to a support such as a transom or mullion of a curtain walling system. Because the fixing inserts are inserted into the outer seal they are easily placed in position and yet ensure a high level of sealing and structural integrity. The outer seal is easily formed and the inserts placed at desired peripherally spaced-apart positions. The toggle which is movable from a locating to a locking position is of relatively simple construction and is easily operated. The glazing assembly is not only easy to install but also by virtue of the fixing means used the integrity of the outer seal is maintained so that the units are able to withstanding high wind loadings. In addition, because of the integrity of the seal with the fixing means used generally less seal is required and the seal sight-lines are thereby improved.
Most preferably the fixing insert is a snug fit to the faces of the adjacent sheets of glass. Because the insert is substantially flush with the inner faces of the glass sheets it is easily fitted and the integrity of sealing is ensured with maximum wind force resistance and load force transfer.
Ideally, the fixing insert is of a material to transmit a load of the glass. The fixing inserts may be of plastics or nylon material.
These features are particularly important in providing inserts of relatively cheap consistent construction which facilitate load transfer to the glass.
In a preferred arrangement the fixing insert has a base wall section, side wall and end wall sections which define the slot for receiving the toggle. Preferably, the slot is of arcuate shape.
This construction of insert is particularly advantageous as in a relatively simple moulded piece an effective fixing is provided. The configuration is particularly suitable to accommodate movement of the toggle on fixing while maintaining structural integrity.
In a preferred embodiment of invention the toggle is rotatable from the locating position to the locking position in which the toggle is engaged in the slots of adjacent inserts. This facilitates a particularly simple method of fixing.
In a preferred arrangement the toggle and a nose portion of a structural element to which it is fitted have complementary interengagable formations to lock the toggle in position relative to the structural member. This provides a more positive. location and fixing of the toggle.
The toggle may have a hole for engagement by a fixing screw which also engages the nose of a structural element on fixing of the toggle. This is a particularly simple location and fixing system.
In one embodiment of the invention the fixing insert includes limiting means for limiting the insertion of the insert into the outer seal.
The limiting means preferably comprises a sidewardly extending flange means. The flange may be continuous or interrupted.
In one embodiment of the invention the fixing insert includes guide means for guiding the insertion of the insert into the outer seal.
The guide means may comprise side ribs extending sidewardly of the fixing insert.
The body of the insert may also be shaped, for example with inclined surfaces to facilitate ease of insertion.
The support may be a mullion or transom of a curtain walling system. The glazing assembly is particularly suited to such a system.
The invention also provides a curtain walling comprising a plurality of glazing assemblies of the invention.